/*
import java.util.Scanner;
    public class Main2 {
        public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            int n, sum;
            while (sc.hasNext()) {
                sum = 0;
                n = sc.nextInt();
                sum = func(n);
                System.out.println(sum);
            }
        }

        public static int func(int n) {
            if (n == 1 || n == 2) return n;
            return func(n - 1) + func(n - 2);
        }

    }
    public static int func(int n){
        if(n==1||n==2) return n-1;
        int sum=0;
        sum+=(func(n)*2+1);
        return sum;
    }
    public static void main1(String[] args) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        int ret=func(n);
        System.out.println(ret);
    }
}
*/
